001 /*
002 * Copyright (C) 2012 eXo Platform SAS.
003 *
004 * This is free software; you can redistribute it and/or modify it
005 * under the terms of the GNU Lesser General Public License as
006 * published by the Free Software Foundation; either version 2.1 of
007 * the License, or (at your option) any later version.
008 *
009 * This software is distributed in the hope that it will be useful,
010 * but WITHOUT ANY WARRANTY; without even the implied warranty of
011 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
012 * Lesser General Public License for more details.
013 *
014 * You should have received a copy of the GNU Lesser General Public
015 * License along with this software; if not, write to the Free
016 * Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
017 * 02110-1301 USA, or see the FSF site: http://www.fsf.org.
018 */
019
020 package org.crsh.text;
021
022 import org.crsh.shell.ScreenContext;
023
024 import java.io.IOException;
025 import java.util.LinkedList;
026
027 public class RenderAppendable implements Appendable, ScreenContext {
028
029 /** . */
030 private final ScreenContext context;
031
032 /** . */
033 private LinkedList<Style.Composite> stack;
034
035 public RenderAppendable(ScreenContext context) {
036 this.context = context;
037 }
038
039 private void safeAppend(Chunk chunk) {
040 try {
041 context.write(chunk);
042 }
043 catch (java.io.IOException e) {
044 // e.printStackTrace();
045 }
046 }
047
048 public void write(Chunk chunk) throws IOException {
049 safeAppend(chunk);
050 }
051
052 public Class<Chunk> getConsumedType() {
053 return Chunk.class;
054 }
055
056 public int getWidth() {
057 // Use one less char to have a correct display on windows
058 return Math.max(0, context.getWidth() - 1);
059 }
060
061 public int getHeight() {
062 return context.getHeight();
063 }
064
065 public void flush() throws IOException {
066 context.flush();
067 }
068
069 public RenderAppendable append(CharSequence csq) {
070 safeAppend(Text.create(csq));
071 return this;
072 }
073
074 public void enterStyle(Style.Composite style) {
075 if (stack == null) {
076 stack = new LinkedList<Style.Composite>();
077 }
078 safeAppend(style);
079 stack.addLast(style);
080 }
081
082 public Style.Composite leaveStyle() {
083 if (stack == null || stack.isEmpty()) {
084 throw new IllegalStateException("Cannot leave non existing style");
085 }
086 Style.Composite last = stack.removeLast();
087 if (stack.size() > 0) {
088
089 // Compute merged
090 Style.Composite merged = getMerged();
091
092 // Compute diff with removed
093 Boolean bold = foo(last.getBold(), merged.getBold());
094 Boolean underline = foo(last.getUnderline(), merged.getUnderline());
095 Boolean blink = foo(last.getBlink(), merged.getBlink());
096
097 // For now we assume that black is the default background color
098 // and white is the default foreground color
099 Color fg = foo(last.getForeground(), merged.getForeground(), Color.def);
100 Color bg = foo(last.getBackground(), merged.getBackground(), Color.def);
101
102 //
103 Style.Composite bilto = Style.style(bold, underline, blink, fg, bg);
104
105 //
106 safeAppend(bilto);
107 } else {
108 safeAppend(Style.reset);
109 }
110 return last;
111 }
112
113 /**
114 * Compute the current merged style.
115 *
116 * @return the merged style
117 */
118 private Style.Composite getMerged() {
119 Style.Composite merged = Style.style();
120 for (Style s : stack) {
121 merged = (Style.Composite)merged.merge(s);
122 }
123 return merged;
124 }
125
126 private Boolean foo(Boolean last, Boolean merged) {
127 if (last != null) {
128 if (merged != null) {
129 return merged;
130 } else {
131 return !last;
132 }
133 } else {
134 return null;
135 }
136 }
137
138 private Color foo(Color last, Color merged, Color def) {
139 if (last != null) {
140 if (merged != null) {
141 return merged;
142 } else {
143 return def;
144 }
145 } else {
146 return null;
147 }
148 }
149
150 public void styleOff() {
151 if (stack != null && stack.size() > 0) {
152 safeAppend(Style.reset);
153 }
154 }
155
156 public void styleOn() {
157 if (stack != null && stack.size() > 0) {
158 safeAppend(getMerged());
159 }
160 }
161
162 public RenderAppendable append(CharSequence csq, int start, int end) {
163 safeAppend(Text.create(csq.subSequence(start, end)));
164 return this;
165 }
166
167 public RenderAppendable append(char c) {
168 safeAppend(Text.create(Character.toString(c)));
169 return this;
170 }
171 }